Regulatory Function of Δ6 Desaturase — Key Enzyme of Polyunsaturated Fatty Acid Synthesis

Abstract

Polyunsaturated fatty acids are synthesized in animals by a sequence of desaturation and elongation reactions which, as we know now, follow special rules. The starting substrates are CoA thioesters of palmitoleic, oleic, linoleic and α linolenic acids. The acyl-CoA synthesis is faster than elongation or desaturation reactions (Marcel and Suzue, 1972). The enzymes involved in the elongation are found either in the endoplasmic reticulum or in mitochondria but the specificity of each group is different. The microsomal system prefers Δ6 unsaturated acyl-CoA and hexanoyl CoA whereas the mitochondrial prefers medium chain acyl-CoA (Podack et al, 1974; Hinsch and Seubert, 1975).